I've written an ASP.Net MVC 3 application using the Code First paradigm whereby when I make a change to the model the Entity Framework automatically attempts to re-create the underlying SQL Server Database via DROP and CREATE statements. The problem is the application is hosted on a 3rd party remote server which limits the number of databases I can have and does not seem to allow me to programmatically execute "CREATE DATABASE..." statements as I gather from this error message:
CREATE DATABASE permission denied in database 'master'.
Is there any way to stop the Entity Framework from dropping and attempting to re-create the whole database and instead make it simply drop the tables and re-create them?
After creating the database manually and running the application I also get the following error I guess as the Entity Framework tries to modify the database:
Model compatibility cannot be checked because the da开发者_如何学Ctabase does not contain model metadata. Ensure that IncludeMetadataConvention has been added to the DbModelBuilder conventions.
UPDATE: Found this gem through google, it sounds like its exactly what you need: http://nuget.org/Tags/IDatabaseInitializer
You can use a different database initializer. Lets say your context is called SampleContext
then your constructor would look like this:
public SampleContext()
{
System.Data.Entity.Database.SetInitializer(new CreateDatabaseIfNotExists<SampleContext>());
}
Note that the above is the default initializer. You will probably need to create your own custom initializer by implementing IDatabaseInitializer
. Theres some good info here: http://sankarsan.wordpress.com/2010/10/14/entity-framework-ctp-4-0-database-initialization/
Using EF 4.3 with Migrations you do not get this behavior - at least I have not seen it. But I also have this set in my code -
public sealed class DbConfiguration : DbMigrationsConfiguration<DatabaseContext>
{
public DbConfiguration()
{
AutomaticMigrationsEnabled = false;
}
}
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